Suspension for tractors



I L ESQA Z2 5. ICKERSHAM SUSPENSION FOR TRACTORS Filed June so, 1920 2sheets-sheet 1 INV EN TOR.

- 1 I x v v A TTORNEY CA EPSH IM Patented Apr. 3, 1 923.

ELMER E. WICKERSHAIMI, 0F STOCKTON, CALIFORNIA, ASSIGNOR TO THE HOLTMANU- FdGTUBING GOME'ANY. 0F STOCKTON, CALIFORNIA, A. CORPORATION, OFCALI- EOBNIA.

SUSPENSION FOR TBACTORS.

Application filed; June 80, 1920. eerie! E0. 392,950.

To all whom it may concern:

Be it known that ELMER E. Wronnnsnam,

acitizen of the United States, residing at' Stockton, inthe county ofSan Joaquin and State of California, has invented new and usefulImprovements in Suspensions for Tractors, of which the following is aspecificatioa. s

' This invention relates tosuspensions for tractors and moreparticularly to tractors of the self-laying track type.

It has for its object to permit the truck mechanisms to rock in avertical plane relatively to the-main frame andvto each other whileimparting little or no movement to the c main frame.

In the accompanying drawings:

Fig. 1 shows aside elevation of a tractor embodying one form of myinvention.

Fig. 2 shows a plan view of a portion of the same. i

Fig. 3 shows a side elevation of the same with the rockingtruck memberin raised position.

Fig. 4 shows a side elevation of a modified form of my invention.

The device here shown comprises a main frame 10 at each side of which isatrack laying unit consisting of a drivingsprocket wheel jou rnaled onan axle 12, which axle is fixed upon the main fra e. The drivingsprocket wheel carries an endless flexible chain track 13 which, at itsforward end, is supported by an idler sprocket wheel 1 1,

The said idler sprocket wheel is journaled on a truck frame 15, whichtruck frame carries a series of rollers '16 for operation on the groundstretch of the track.

Pivoted upon each end of the axle 12 is a swinging thrust member 17extending forwardly and pivotally connected at'18 to the adjacent truckframe.

As shown in Figs. 1 to 3 inclusive,the pivotal connection 18 is arrangednear the rear end of the truck frame and at the forward end of theswinging thrust member is a cam nected with the truck frame by means ora link 21*.

In operation itwilLbe seen that as the forward end of the truck frame israised in passing over an obstruction, the cam 19 will when the truckframe is rocked and consequently the connection 18 changes itselevation, there will be no change in the elevation of the main frameowing to the shorter radius of that portion of the cam which comesbeneaththe main frame when the-truck frame is rocked.

Various changes in the construction and arrangement of the'several partsmay be employed without departing from the spirit of my invention asdisclosed in the appended claims.

Having thus described my invention, what I claim and desire to secure byLetters Patent is: 1

1. Ina vehicle of the self-laying track type, a main frame, a truckframe at each side thereof, connecting means between the truck frameiandthe main frame,permitting said truck frame to rock in a vertical plane,and a load supporting connection between the truck frame and adjacent.side of the main frame controlled by the rocking movement of the truckframe-to permit the'latter to rise without efi'ectingany change in thement in a vertical plane, and a loadsup- Eur-ting connection between thetruck memer and main frame comprising a cam turn-. able with the truckmember when the letter endso shaped as to maintain the main upon themain fraine, a driving sprocket Wheel carried by the axle, a swingingthrust member pivotnlly connected to the axle, a truck member pivotallyconnected with the swinging thrust member for rocking movement in avertical plane, and a load supporting connection between the trnck'member and main frame comprising a cam mounted for rocking movement onthe forward end of the swinging thrust member and having connectionswith the truckrmeniber to cause the can: to he turned so as to present ashorter radius when the forward-end of the truck member is moved. ups;illy.

4. In a vehicle, a main frame, a. track-laymg unit at each side thereof,including a truck frame connected with the main frame forrockingmovement in a vertical plane,

and a load bearing connection between the truck frame and the mainframe, comprismg a cam connected with the truck frame and movable whenthe latter rocks, so as to ELMER E. 'WECKERSHAM.

Witnesses:

DAVID B. LYMAN, EDWARD E. Ban TENLUCHER.

